| 1 | /* |
| 2 | SDL - Simple DirectMedia Layer |
| 3 | Copyright (C) 1997-2009 Sam Lantinga |
| 4 | |
| 5 | This library is free software; you can redistribute it and/or |
| 6 | modify it under the terms of the GNU Lesser General Public |
| 7 | License as published by the Free Software Foundation; either |
| 8 | version 2.1 of the License, or (at your option) any later version. |
| 9 | |
| 10 | This library is distributed in the hope that it will be useful, |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 13 | Lesser General Public License for more details. |
| 14 | |
| 15 | You should have received a copy of the GNU Lesser General Public |
| 16 | License along with this library; if not, write to the Free Software |
| 17 | Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA |
| 18 | |
| 19 | Sam Lantinga |
| 20 | slouken@libsdl.org |
| 21 | */ |
| 22 | #include "SDL_config.h" |
| 23 | |
| 24 | /* General event handling code for SDL */ |
| 25 | |
| 26 | #include "SDL.h" |
| 27 | #include "SDL_syswm.h" |
| 28 | #include "SDL_sysevents.h" |
| 29 | #include "SDL_events_c.h" |
| 30 | #include "../timer/SDL_timer_c.h" |
| 31 | #if !SDL_JOYSTICK_DISABLED |
| 32 | #include "../joystick/SDL_joystick_c.h" |
| 33 | #endif |
| 34 | |
| 35 | /* Public data -- the event filter */ |
| 36 | SDL_EventFilter SDL_EventOK = NULL; |
| 37 | Uint8 SDL_ProcessEvents[SDL_NUMEVENTS]; |
| 38 | static Uint32 SDL_eventstate = 0; |
| 39 | |
| 40 | /* Private data -- event queue */ |
| 41 | #define MAXEVENTS 128 |
| 42 | static struct { |
| 43 | SDL_mutex *lock; |
| 44 | int active; |
| 45 | int head; |
| 46 | int tail; |
| 47 | SDL_Event event[MAXEVENTS]; |
| 48 | int wmmsg_next; |
| 49 | struct SDL_SysWMmsg wmmsg[MAXEVENTS]; |
| 50 | } SDL_EventQ; |
| 51 | |
| 52 | /* Private data -- event locking structure */ |
| 53 | static struct { |
| 54 | SDL_mutex *lock; |
| 55 | int safe; |
| 56 | } SDL_EventLock; |
| 57 | |
| 58 | /* Thread functions */ |
| 59 | static SDL_Thread *SDL_EventThread = NULL; /* Thread handle */ |
| 60 | static Uint32 event_thread; /* The event thread id */ |
| 61 | |
| 62 | void SDL_Lock_EventThread(void) |
| 63 | { |
| 64 | if ( SDL_EventThread && (SDL_ThreadID() != event_thread) ) { |
| 65 | /* Grab lock and spin until we're sure event thread stopped */ |
| 66 | SDL_mutexP(SDL_EventLock.lock); |
| 67 | while ( ! SDL_EventLock.safe ) { |
| 68 | SDL_Delay(1); |
| 69 | } |
| 70 | } |
| 71 | } |
| 72 | void SDL_Unlock_EventThread(void) |
| 73 | { |
| 74 | if ( SDL_EventThread && (SDL_ThreadID() != event_thread) ) { |
| 75 | SDL_mutexV(SDL_EventLock.lock); |
| 76 | } |
| 77 | } |
| 78 | |
| 79 | #ifdef __OS2__ |
| 80 | /* |
| 81 | * We'll increase the priority of GobbleEvents thread, so it will process |
| 82 | * events in time for sure! For this, we need the DosSetPriority() API |
| 83 | * from the os2.h include file. |
| 84 | */ |
| 85 | #define INCL_DOSPROCESS |
| 86 | #include <os2.h> |
| 87 | #include <time.h> |
| 88 | #endif |
| 89 | |
| 90 | static int SDLCALL SDL_GobbleEvents(void *unused) |
| 91 | { |
| 92 | event_thread = SDL_ThreadID(); |
| 93 | |
| 94 | #ifdef __OS2__ |
| 95 | #ifdef USE_DOSSETPRIORITY |
| 96 | /* Increase thread priority, so it will process events in time for sure! */ |
| 97 | DosSetPriority(PRTYS_THREAD, PRTYC_REGULAR, +16, 0); |
| 98 | #endif |
| 99 | #endif |
| 100 | |
| 101 | while ( SDL_EventQ.active ) { |
| 102 | SDL_VideoDevice *video = current_video; |
| 103 | SDL_VideoDevice *this = current_video; |
| 104 | |
| 105 | /* Get events from the video subsystem */ |
| 106 | if ( video ) { |
| 107 | video->PumpEvents(this); |
| 108 | } |
| 109 | |
| 110 | /* Queue pending key-repeat events */ |
| 111 | SDL_CheckKeyRepeat(); |
| 112 | |
| 113 | #if !SDL_JOYSTICK_DISABLED |
| 114 | /* Check for joystick state change */ |
| 115 | if ( SDL_numjoysticks && (SDL_eventstate & SDL_JOYEVENTMASK) ) { |
| 116 | SDL_JoystickUpdate(); |
| 117 | } |
| 118 | #endif |
| 119 | |
| 120 | /* Give up the CPU for the rest of our timeslice */ |
| 121 | SDL_EventLock.safe = 1; |
| 122 | if ( SDL_timer_running ) { |
| 123 | SDL_ThreadedTimerCheck(); |
| 124 | } |
| 125 | SDL_Delay(1); |
| 126 | |
| 127 | /* Check for event locking. |
| 128 | On the P of the lock mutex, if the lock is held, this thread |
| 129 | will wait until the lock is released before continuing. The |
| 130 | safe flag will be set, meaning that the other thread can go |
| 131 | about it's business. The safe flag is reset before the V, |
| 132 | so as soon as the mutex is free, other threads can see that |
| 133 | it's not safe to interfere with the event thread. |
| 134 | */ |
| 135 | SDL_mutexP(SDL_EventLock.lock); |
| 136 | SDL_EventLock.safe = 0; |
| 137 | SDL_mutexV(SDL_EventLock.lock); |
| 138 | } |
| 139 | SDL_SetTimerThreaded(0); |
| 140 | event_thread = 0; |
| 141 | return(0); |
| 142 | } |
| 143 | |
| 144 | static int SDL_StartEventThread(Uint32 flags) |
| 145 | { |
| 146 | /* Reset everything to zero */ |
| 147 | SDL_EventThread = NULL; |
| 148 | SDL_memset(&SDL_EventLock, 0, sizeof(SDL_EventLock)); |
| 149 | |
| 150 | /* Create the lock and set ourselves active */ |
| 151 | #if !SDL_THREADS_DISABLED |
| 152 | SDL_EventQ.lock = SDL_CreateMutex(); |
| 153 | if ( SDL_EventQ.lock == NULL ) { |
| 154 | #ifdef __MACOS__ /* MacOS classic you can't multithread, so no lock needed */ |
| 155 | ; |
| 156 | #else |
| 157 | return(-1); |
| 158 | #endif |
| 159 | } |
| 160 | #endif /* !SDL_THREADS_DISABLED */ |
| 161 | SDL_EventQ.active = 1; |
| 162 | |
| 163 | if ( (flags&SDL_INIT_EVENTTHREAD) == SDL_INIT_EVENTTHREAD ) { |
| 164 | SDL_EventLock.lock = SDL_CreateMutex(); |
| 165 | if ( SDL_EventLock.lock == NULL ) { |
| 166 | return(-1); |
| 167 | } |
| 168 | SDL_EventLock.safe = 0; |
| 169 | |
| 170 | /* The event thread will handle timers too */ |
| 171 | SDL_SetTimerThreaded(2); |
| 172 | #if (defined(__WIN32__) && !defined(_WIN32_WCE)) && !defined(HAVE_LIBC) && !defined(__SYMBIAN32__) |
| 173 | #undef SDL_CreateThread |
| 174 | SDL_EventThread = SDL_CreateThread(SDL_GobbleEvents, NULL, NULL, NULL); |
| 175 | #else |
| 176 | SDL_EventThread = SDL_CreateThread(SDL_GobbleEvents, NULL); |
| 177 | #endif |
| 178 | if ( SDL_EventThread == NULL ) { |
| 179 | return(-1); |
| 180 | } |
| 181 | } else { |
| 182 | event_thread = 0; |
| 183 | } |
| 184 | return(0); |
| 185 | } |
| 186 | |
| 187 | static void SDL_StopEventThread(void) |
| 188 | { |
| 189 | SDL_EventQ.active = 0; |
| 190 | if ( SDL_EventThread ) { |
| 191 | SDL_WaitThread(SDL_EventThread, NULL); |
| 192 | SDL_EventThread = NULL; |
| 193 | SDL_DestroyMutex(SDL_EventLock.lock); |
| 194 | SDL_EventLock.lock = NULL; |
| 195 | } |
| 196 | #ifndef IPOD |
| 197 | SDL_DestroyMutex(SDL_EventQ.lock); |
| 198 | SDL_EventQ.lock = NULL; |
| 199 | #endif |
| 200 | } |
| 201 | |
| 202 | Uint32 SDL_EventThreadID(void) |
| 203 | { |
| 204 | return(event_thread); |
| 205 | } |
| 206 | |
| 207 | /* Public functions */ |
| 208 | |
| 209 | void SDL_StopEventLoop(void) |
| 210 | { |
| 211 | /* Halt the event thread, if running */ |
| 212 | SDL_StopEventThread(); |
| 213 | |
| 214 | /* Shutdown event handlers */ |
| 215 | SDL_AppActiveQuit(); |
| 216 | SDL_KeyboardQuit(); |
| 217 | SDL_MouseQuit(); |
| 218 | SDL_QuitQuit(); |
| 219 | |
| 220 | /* Clean out EventQ */ |
| 221 | SDL_EventQ.head = 0; |
| 222 | SDL_EventQ.tail = 0; |
| 223 | SDL_EventQ.wmmsg_next = 0; |
| 224 | } |
| 225 | |
| 226 | /* This function (and associated calls) may be called more than once */ |
| 227 | int SDL_StartEventLoop(Uint32 flags) |
| 228 | { |
| 229 | int retcode; |
| 230 | |
| 231 | /* Clean out the event queue */ |
| 232 | SDL_EventThread = NULL; |
| 233 | SDL_EventQ.lock = NULL; |
| 234 | SDL_StopEventLoop(); |
| 235 | |
| 236 | /* No filter to start with, process most event types */ |
| 237 | SDL_EventOK = NULL; |
| 238 | SDL_memset(SDL_ProcessEvents,SDL_ENABLE,sizeof(SDL_ProcessEvents)); |
| 239 | SDL_eventstate = ~0; |
| 240 | /* It's not save to call SDL_EventState() yet */ |
| 241 | SDL_eventstate &= ~(0x00000001 << SDL_SYSWMEVENT); |
| 242 | SDL_ProcessEvents[SDL_SYSWMEVENT] = SDL_IGNORE; |
| 243 | |
| 244 | /* Initialize event handlers */ |
| 245 | retcode = 0; |
| 246 | retcode += SDL_AppActiveInit(); |
| 247 | retcode += SDL_KeyboardInit(); |
| 248 | retcode += SDL_MouseInit(); |
| 249 | retcode += SDL_QuitInit(); |
| 250 | if ( retcode < 0 ) { |
| 251 | /* We don't expect them to fail, but... */ |
| 252 | return(-1); |
| 253 | } |
| 254 | |
| 255 | /* Create the lock and event thread */ |
| 256 | if ( SDL_StartEventThread(flags) < 0 ) { |
| 257 | SDL_StopEventLoop(); |
| 258 | return(-1); |
| 259 | } |
| 260 | return(0); |
| 261 | } |
| 262 | |
| 263 | |
| 264 | /* Add an event to the event queue -- called with the queue locked */ |
| 265 | static int SDL_AddEvent(SDL_Event *event) |
| 266 | { |
| 267 | int tail, added; |
| 268 | |
| 269 | tail = (SDL_EventQ.tail+1)%MAXEVENTS; |
| 270 | if ( tail == SDL_EventQ.head ) { |
| 271 | /* Overflow, drop event */ |
| 272 | added = 0; |
| 273 | } else { |
| 274 | SDL_EventQ.event[SDL_EventQ.tail] = *event; |
| 275 | if (event->type == SDL_SYSWMEVENT) { |
| 276 | /* Note that it's possible to lose an event */ |
| 277 | int next = SDL_EventQ.wmmsg_next; |
| 278 | SDL_EventQ.wmmsg[next] = *event->syswm.msg; |
| 279 | SDL_EventQ.event[SDL_EventQ.tail].syswm.msg = |
| 280 | &SDL_EventQ.wmmsg[next]; |
| 281 | SDL_EventQ.wmmsg_next = (next+1)%MAXEVENTS; |
| 282 | } |
| 283 | SDL_EventQ.tail = tail; |
| 284 | added = 1; |
| 285 | } |
| 286 | return(added); |
| 287 | } |
| 288 | |
| 289 | /* Cut an event, and return the next valid spot, or the tail */ |
| 290 | /* -- called with the queue locked */ |
| 291 | static int SDL_CutEvent(int spot) |
| 292 | { |
| 293 | if ( spot == SDL_EventQ.head ) { |
| 294 | SDL_EventQ.head = (SDL_EventQ.head+1)%MAXEVENTS; |
| 295 | return(SDL_EventQ.head); |
| 296 | } else |
| 297 | if ( (spot+1)%MAXEVENTS == SDL_EventQ.tail ) { |
| 298 | SDL_EventQ.tail = spot; |
| 299 | return(SDL_EventQ.tail); |
| 300 | } else |
| 301 | /* We cut the middle -- shift everything over */ |
| 302 | { |
| 303 | int here, next; |
| 304 | |
| 305 | /* This can probably be optimized with SDL_memcpy() -- careful! */ |
| 306 | if ( --SDL_EventQ.tail < 0 ) { |
| 307 | SDL_EventQ.tail = MAXEVENTS-1; |
| 308 | } |
| 309 | for ( here=spot; here != SDL_EventQ.tail; here = next ) { |
| 310 | next = (here+1)%MAXEVENTS; |
| 311 | SDL_EventQ.event[here] = SDL_EventQ.event[next]; |
| 312 | } |
| 313 | return(spot); |
| 314 | } |
| 315 | /* NOTREACHED */ |
| 316 | } |
| 317 | |
| 318 | /* Lock the event queue, take a peep at it, and unlock it */ |
| 319 | int SDL_PeepEvents(SDL_Event *events, int numevents, SDL_eventaction action, |
| 320 | Uint32 mask) |
| 321 | { |
| 322 | int i, used; |
| 323 | |
| 324 | /* Don't look after we've quit */ |
| 325 | if ( ! SDL_EventQ.active ) { |
| 326 | return(-1); |
| 327 | } |
| 328 | /* Lock the event queue */ |
| 329 | used = 0; |
| 330 | if ( SDL_mutexP(SDL_EventQ.lock) == 0 ) { |
| 331 | if ( action == SDL_ADDEVENT ) { |
| 332 | for ( i=0; i<numevents; ++i ) { |
| 333 | used += SDL_AddEvent(&events[i]); |
| 334 | } |
| 335 | } else { |
| 336 | SDL_Event tmpevent; |
| 337 | int spot; |
| 338 | |
| 339 | /* If 'events' is NULL, just see if they exist */ |
| 340 | if ( events == NULL ) { |
| 341 | action = SDL_PEEKEVENT; |
| 342 | numevents = 1; |
| 343 | events = &tmpevent; |
| 344 | } |
| 345 | spot = SDL_EventQ.head; |
| 346 | while ((used < numevents)&&(spot != SDL_EventQ.tail)) { |
| 347 | if ( mask & SDL_EVENTMASK(SDL_EventQ.event[spot].type) ) { |
| 348 | events[used++] = SDL_EventQ.event[spot]; |
| 349 | if ( action == SDL_GETEVENT ) { |
| 350 | spot = SDL_CutEvent(spot); |
| 351 | } else { |
| 352 | spot = (spot+1)%MAXEVENTS; |
| 353 | } |
| 354 | } else { |
| 355 | spot = (spot+1)%MAXEVENTS; |
| 356 | } |
| 357 | } |
| 358 | } |
| 359 | SDL_mutexV(SDL_EventQ.lock); |
| 360 | } else { |
| 361 | SDL_SetError("Couldn't lock event queue"); |
| 362 | used = -1; |
| 363 | } |
| 364 | return(used); |
| 365 | } |
| 366 | |
| 367 | /* Run the system dependent event loops */ |
| 368 | void SDL_PumpEvents(void) |
| 369 | { |
| 370 | if ( !SDL_EventThread ) { |
| 371 | SDL_VideoDevice *video = current_video; |
| 372 | SDL_VideoDevice *this = current_video; |
| 373 | |
| 374 | /* Get events from the video subsystem */ |
| 375 | if ( video ) { |
| 376 | video->PumpEvents(this); |
| 377 | } |
| 378 | |
| 379 | /* Queue pending key-repeat events */ |
| 380 | SDL_CheckKeyRepeat(); |
| 381 | |
| 382 | #if !SDL_JOYSTICK_DISABLED |
| 383 | /* Check for joystick state change */ |
| 384 | if ( SDL_numjoysticks && (SDL_eventstate & SDL_JOYEVENTMASK) ) { |
| 385 | SDL_JoystickUpdate(); |
| 386 | } |
| 387 | #endif |
| 388 | } |
| 389 | } |
| 390 | |
| 391 | /* Public functions */ |
| 392 | |
| 393 | int SDL_PollEvent (SDL_Event *event) |
| 394 | { |
| 395 | SDL_PumpEvents(); |
| 396 | |
| 397 | /* We can't return -1, just return 0 (no event) on error */ |
| 398 | if ( SDL_PeepEvents(event, 1, SDL_GETEVENT, SDL_ALLEVENTS) <= 0 ) |
| 399 | return 0; |
| 400 | return 1; |
| 401 | } |
| 402 | |
| 403 | int SDL_WaitEvent (SDL_Event *event) |
| 404 | { |
| 405 | while ( 1 ) { |
| 406 | SDL_PumpEvents(); |
| 407 | switch(SDL_PeepEvents(event, 1, SDL_GETEVENT, SDL_ALLEVENTS)) { |
| 408 | case -1: return 0; |
| 409 | case 1: return 1; |
| 410 | case 0: SDL_Delay(10); |
| 411 | } |
| 412 | } |
| 413 | } |
| 414 | |
| 415 | int SDL_PushEvent(SDL_Event *event) |
| 416 | { |
| 417 | if ( SDL_PeepEvents(event, 1, SDL_ADDEVENT, 0) <= 0 ) |
| 418 | return -1; |
| 419 | return 0; |
| 420 | } |
| 421 | |
| 422 | void SDL_SetEventFilter (SDL_EventFilter filter) |
| 423 | { |
| 424 | SDL_Event bitbucket; |
| 425 | |
| 426 | /* Set filter and discard pending events */ |
| 427 | SDL_EventOK = filter; |
| 428 | while ( SDL_PollEvent(&bitbucket) > 0 ) |
| 429 | ; |
| 430 | } |
| 431 | |
| 432 | SDL_EventFilter SDL_GetEventFilter(void) |
| 433 | { |
| 434 | return(SDL_EventOK); |
| 435 | } |
| 436 | |
| 437 | Uint8 SDL_EventState (Uint8 type, int state) |
| 438 | { |
| 439 | SDL_Event bitbucket; |
| 440 | Uint8 current_state; |
| 441 | |
| 442 | /* If SDL_ALLEVENTS was specified... */ |
| 443 | if ( type == 0xFF ) { |
| 444 | current_state = SDL_IGNORE; |
| 445 | for ( type=0; type<SDL_NUMEVENTS; ++type ) { |
| 446 | if ( SDL_ProcessEvents[type] != SDL_IGNORE ) { |
| 447 | current_state = SDL_ENABLE; |
| 448 | } |
| 449 | SDL_ProcessEvents[type] = state; |
| 450 | if ( state == SDL_ENABLE ) { |
| 451 | SDL_eventstate |= (0x00000001 << (type)); |
| 452 | } else { |
| 453 | SDL_eventstate &= ~(0x00000001 << (type)); |
| 454 | } |
| 455 | } |
| 456 | while ( SDL_PollEvent(&bitbucket) > 0 ) |
| 457 | ; |
| 458 | return(current_state); |
| 459 | } |
| 460 | |
| 461 | /* Just set the state for one event type */ |
| 462 | current_state = SDL_ProcessEvents[type]; |
| 463 | switch (state) { |
| 464 | case SDL_IGNORE: |
| 465 | case SDL_ENABLE: |
| 466 | /* Set state and discard pending events */ |
| 467 | SDL_ProcessEvents[type] = state; |
| 468 | if ( state == SDL_ENABLE ) { |
| 469 | SDL_eventstate |= (0x00000001 << (type)); |
| 470 | } else { |
| 471 | SDL_eventstate &= ~(0x00000001 << (type)); |
| 472 | } |
| 473 | while ( SDL_PollEvent(&bitbucket) > 0 ) |
| 474 | ; |
| 475 | break; |
| 476 | default: |
| 477 | /* Querying state? */ |
| 478 | break; |
| 479 | } |
| 480 | return(current_state); |
| 481 | } |
| 482 | |
| 483 | /* This is a generic event handler. |
| 484 | */ |
| 485 | int SDL_PrivateSysWMEvent(SDL_SysWMmsg *message) |
| 486 | { |
| 487 | int posted; |
| 488 | |
| 489 | posted = 0; |
| 490 | if ( SDL_ProcessEvents[SDL_SYSWMEVENT] == SDL_ENABLE ) { |
| 491 | SDL_Event event; |
| 492 | SDL_memset(&event, 0, sizeof(event)); |
| 493 | event.type = SDL_SYSWMEVENT; |
| 494 | event.syswm.msg = message; |
| 495 | if ( (SDL_EventOK == NULL) || (*SDL_EventOK)(&event) ) { |
| 496 | posted = 1; |
| 497 | SDL_PushEvent(&event); |
| 498 | } |
| 499 | } |
| 500 | /* Update internal event state */ |
| 501 | return(posted); |
| 502 | } |